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Reasonably designing and synthesizing advanced electrode materials is significant to enhance the electrochemical performance of lithium ion batteries (LIBs). Herein, a metal–organic framework (MOF, Mil‐125) was used as a precursor and template to successfully synthesize the porous mooncake‐shaped Li4Ti5O12 (LTO) anode material assembled from nanoparticles. Even more critical, SmF3 was used to modify the prepared porous mooncake‐shaped LTO material. The SmF3‐modified LTO maintained a porous mooncake‐shaped structure with a large specific surface area, and the SmF3 nanoparticles were observed to be attach on the surface of the LTO material. It has been proven that the SmF3 modification can further facilitate the transition from Ti4+ to Ti3+, reduce the polarization of electrode, decrease charge transfer impedance (Rct) and solid electrolyte interface impedance (Rsei), and increase the lithium ion diffusion coefficient (DLi), thereby enhancing the electrochemical performance of LTO. Therefore, the porous mooncake‐shaped LTO modified using 2 wt % SmF3 displays a large specific discharge capacity of 143.8 mAh g−1 with an increment of 79.16 % compared to pure LTO at a high rate of 10 C (1 C=170 mAh g−1), and shows a high retention rate of 96.4 % after 500 cycles at 5 C‐rate. [ABSTRACT FROM AUTHOR]

[Display omitted] • Polyaniline coated hollow mesopore hard carbon spheres are precisely tailored. • Polyaniline coating greatly boosts conductivity, while keeping considerable mesopores. • Polyaniline coating helps to form a stable and inorganic-rich SEI layer. • An excellent rate capacity (233.9 mAh g−1 at 5 A g−1) and a high ICE (70.7%) are realized. Hard carbon with rich mesopores is considered as one of the most promising anodes for potassium-ion batteries, resulting from its shortened ions diffusion distance, good electrolyte penetration ability, and highly released stress. However, the well-developed pore channels tend to separate graphite-domains and enlarge direct contact area between electrode/electrolyte, which easily cause discontinuous electrons transfer paths and extra electrolyte depletion, thus leading to poor rate performance and initial Coulombic efficiency (ICE). Hence, we propose polyaniline conductive layer coated hollow mesoporous carbon spheres (HMCS@PAN) tailored based on local protonation reaction strategy, which can enhance conductivity and simultaneously maintain considerable pore structure, accounting for an ultrahigh-rate performance (233.9 mAh/g at 5 A/g) and long cycling life (216.8 mAh/g at 5 A/g over 2000 cycles). Besides, PAN coating can inhibit the direct contact between inner pore channels and electrolyte and reduce the excessive depletion of active ions in the filling of pores with larger pore size, which is conducive to building an even, stable, and inorganic-rich solid electrolyte interphase (SEI) layer, resulting in an excellent ICE (70.7%). This work provides a guidance for the structure design of mesopore hard carbon to improve its rate and ICE. [ABSTRACT FROM AUTHOR]

Carbon layers and pores are important sodium storage sites. The amount and morphology of micropores were regulated by controlling the dosage of zinc acetate. Besides, the proper matching of carbon layers and micropores promotes the extreme capacity of hard carbons. [Display omitted] • The content and morphology of micropores were regulated by zinc acetate. • The "insertion" and "pore-filling" mechanisms maximize sodium storage capacity. • The optimized electrode provided an ultra-high reversible capacity of 415.3 mAh/g and excellent cycle stability. Hard carbons are classic anode materials for sodium-ion batteries (SIBs) with huge development potential. They have the advantages of high capacity and great stability. However, the complex and diverse structure poses a formidable challenge for the development of hard carbons. Carbon layers and pores are important components of hard carbons, they play important roles in sodium storage. Structural regulation is often used to improve the properties of hard carbons in order to enhance the sodium storage capacity. Hence, a series of hard carbons were prepared in this work. Zinc acetate was used to construct micropore structure, and the amount and morphology of micropores can be regulated by controlling the dosage of zinc acetate. The sodium storage capacity of hard carbons was maximized by adjusting the ratio of carbon layers to micropores reasonably. The optimized electrode can provide an ultra-high reversible capacity of 415.3 mAh/g. The amazing capacity can still maintain 292.2 mAh/g even at the high current of 2 A/g over 1000 cycles. This study regulates the proper control between carbon layers and micropores, which provides suitable insights for the research and development of hard carbons. [ABSTRACT FROM AUTHOR]

The mechanism of O-doping on the electrochemical behavior of activated carbon has been clearly revealed. [Display omitted] • A mild oxidation way was adopted to achieve the O-doping on the activated carbon. • The O-doping is correlated with the quasi capacitance of active materials. • Introducing the C-O and COOH functional groups can improve the wettability of AC. O-doping is important to regulate the electrochemical behavior of activated carbon (AC) used in supercapacitors. However, the clear mechanism and relationship of O-doping on the capacitance behavior of AC seem contradictory and remain undisclosed. This is because when O-doping is carried out, it often causes changes in the physical and chemical properties such as defect state, structure, and specific surface area of AC. The superposition of these factors on capacitance behavior complicates the research problem. Here, a low-temperature oxidation method was adopted to achieve doping of different forms of O-functional groups on the AC with minimal effect on its structure and specific surface area. It can be found that the effect of O-doping on the double-layer capacitance of AC is relatively small, but positively correlated with the pseudocapacitance. This is because the functional groups C-O and COOH by O-doping can not only improve the wettability between the electrolyte and AC, but also combine with cations in the electrolyte to enhance the pseudo capacitance. The influence mechanism of O-doping on the capacitance behavior of AC has been verified in different electrode systems and aqueous electrolytes. This study provides theoretical support for rational O-doping to enhance the electrochemical performance of AC. [ABSTRACT FROM AUTHOR]

Nano-silicon (n-Si)/graphite anodes are highly desirable for high-energy lithium-ion batteries. Nevertheless, the high surface energy of n-Si grains is prone to causing serious agglomeration. In this work, the modified n-Si is evenly dispersed on the g-C 3 N 4 carbon mesh that acquired through melamine heat treatment constructing an adaptive Si-carbon interconnection network structure (mSi 50 /g-C 3 N 4). Ideally, the mSi 50 /g-C 3 N 4 composite can be well dispersed and fill the gaps in graphite through traditional ball milling processes. The obtained mSi 50 /g-C 3 N 4 /Gr composite prevents the accumulation of Si grains which is beneficial for expediting ion transport, improving conductivity and structural stability. As a result, this anode provides a reversible capacity of 621 mAh⋅g−1 at 0.2 C, with high-capacity retention of 93.3 % after 300 cycles at 1 C and low volume expansion of only 28.6 %. Furthermore, it also maintains excellent cycling stability in full batteries with LiFePO 4 cathode. Therefore, constructing the mSi 50 /g-C 3 N 4 network is an effective strategy to achieve uniform dispersion of Si in graphite and promote larger scale industrialization of n-Si/graphite anode. The adaptive Si-carbon interconnection network structure was achieved, which is dedicated to the uniform dispersion of Si on the surface of graphite. [Display omitted] • The mSi 50 /g-C 3 N 4 is obtained by dispersing of modified Si on g-C 3 N 4 carbon mesh that acquired through melamine treatment. • The mSi 50 /g-C 3 N 4 /Gr composite prevents the accumulation of Si grains which is beneficial for expediting ion transport. • The mSi 50 /g-C 3 N 4 /Gr provides a capacity of 621 mAh⋅g−1 at 0.2 C, with a retention rate of 93.3 % after 300 cycles. [ABSTRACT FROM AUTHOR]

• Sc(OTf) 3 eliminates the effect of NO 3 − on DOL ring-opening polymerization. • The gel-polymer-electrolyte exhibits high ionic conductivity and t Li + . • Construction of Li 3 N-rich interfacial layers to protect electrodes and electrolytes. • Construction of a new internal model for a new polymer lithium metal battery. 1,3-Dioxolane (DOL) can be induced to form polymer electrolytes by in situ ring opening polymerization at Lewis acid salts. However, the presence of ion–dipole interactions between NO 3 − and DOL suppresses this polymerization behavior. Herein, we report that the use of Sc(OTf) 3 as an initiator can well disrupt this ion–dipole interaction. The in situ ring-opening polymerization of DOL is achieved to form a LiNO 3 -modified polyDOL-based electrolyte. New mechanism of Li migration in polymer electrolytes have been revealed by molecular dynamics modeling and constructed molecular interface models. It is found that the electrolyte interior is affected by the ion–dipole interactions of Li+ by NO 3 −, which made it easier for Li+ to be released from the polar ether-oxygen ligands on the polymer chain for rapid migration, thus exhibiting an ionic conductivity of 1.8 mS cm−1 and t Li + of 0.78. In addition, NO 3 − preempts the binding sites around Li+, improves the coordination environment, and prioritizes the formation of a kinetically stable anion-derivative interface, which effectively mitigates the interfacial side reactions between the electrodes and the electrolytes. As a result, the assembled solid-state Li||LiFePO 4 cell exhibits an impressive 152.3 mAh/g discharge capacity at 0.5C and maintains 80.3 % of the capacity after 450 cycles at 50 °C. This work not only opens a new avenue for designing high-performance gel polymer electrolytes for more metal-based batteries, but also provides valuable insights into understanding the ion migration mechanism. [ABSTRACT FROM AUTHOR]

Boron (B) and nitrogen (N) co-doped hard carbons usually tend to deliver an excellent rate and ultra-long cycle lifespan, because of the formed B-N moieties can accelerate both ion/electron transfer. However, the rational regulation of B-N moieties content is rarely mentioned, and correlating rate and reversible capacity with B-N moieties content is still lacking yet. Hence, a series of B/N co-doped hard carbons are designed based on varied carbonization temperatures. Systematic characterizations prove that the introduced B-heteroatoms can create more defects and form well-developed pore channels. Besides, with increasing carbonization temperatures, B-N moieties content first increases and then decreases, which is in accordance with the evolution of defect degree of carbon matrix. Therefore, rich B-N moieties can induce more defect sites to greatly improve capacitive contribution, and as a result both rate and reversible capacity are strongly correlated with B-N moieties content. Based on this, the electrode with the highest B-N moieties content (79.6 %) realizes an excellent rate (220.9 mAh g−1 at 2 A g−1) and cycling stability (over 2000 cycles). Note that the storage of B-N moieties on K + only occurs in a high potential region (>0.5 V), and this process is highly reversible. [ABSTRACT FROM AUTHOR]

[Display omitted] • P-O rather than P-C species are positively correlated with carbon interlayer spacing. • An expanded interspacing can allow more K-ions to insertion and accelerate them transfer. • The resulting products realize an excellent rate and high capacity, especially plateau capacity. Implanted phosphorus (P) atoms can greatly broaden carbon interlayer spacing and boost defect content, thus resulting in increased rate and capacity; however, different P-species (e.g., P-C and P-O) are how to affect interspacing and defect still remains unclear, and needs to be fundamentally explored. Herein, carbon materials with controllable P-C and P-O moieties (denoted as PNC-900-T, T = 0.2, 0.3, and 0.4) are first synthesized via a gas-steaming route. Detailed experimental analyses demonstrate that P-O species are positively correlated with interspacing, while P-C bonds devote more to enhancing defect. Besides, the introduced P-dopants can trigger the evolution of pore architecture from mesopores to micro/mesopores mixing and then to micropores. As such, the PNC-900–0.3 with the highest P-O proportion (74.8%) realizes the largest interspacing (0.377 nm), thus enabling more K-ions insertion and accelerating their migration. And its defect and micropores can function as active sites to promote the adsorption storage of K-ions. All these together contribute to high capacity, rate (232.3 mAh/g at 2 A/g), and a prolonged cycle lifespan (230.2 mAh/g over 2000 cycles). The effects of different P configurations on microstructure identified by this work provide an insight into the synthesis of other P-functionalized carbon. [ABSTRACT FROM AUTHOR]

• A series of FEC modified gel polymer electrolytes have been successfully prepared by one-step in-situ polymerization. • By adjusting the FEC content, a stable NaF-rich interface is formed between the electrolyte and the electrode. • Matching Na 3 V 2 (PO 4) 3 cathode delivers excellent cycling stability, with a capacity retention of 95.31% over 1000 cycles at 5 c. Sodium metal batteries (SMBs) are considered feasible candidate for large-scale energy systems. However, complicated reactions between the electrode and electrolyte in liquid electrolyte system lead to poor performance and significant safety issues. Therefore, constructing stable electrode-electrolyte interface is necessary to enhance the comprehensive performance of cells. Utilizing gel polymer electrolytes (GPEs) by in-situ polymerization and moderate additive can effectively address these problems. Herein, a series of fluoroethylene carbonate (FEC) modified GPEs have been successfully prepared by one-step in-situ polymerization, in which trimethylolpropane trimethyl acrylate (TMPTMA) and 1,6-hexanediol diacrylate (HDDA) were used as polymer monomers. As a result, the as-optimized electrolyte, THDP-FEC-2%, exhibited high ionic conductivity (3.77 × 10−3 S cm−1) at 25 °C, high Na+ migration number (0.41), and broad electrochemical window (4.6 V). Encouragingly, the NVP|THDP-FEC-2%|Na cell even exhibited ultra-long cycling stability at high rate (95.31% capacity retention at 5C after 1000 cycles). Such excellent electrochemical performances are attributed to the successful establishment of uniform and dense NaF-rich solid electrolyte interface protection layer. This work is expected to offer interface soft protection layer tuned strategy to construct the ideal interface for high-performance SMBs. [Display omitted] [ABSTRACT FROM AUTHOR]

The reported synthesis methods classified by raw materials and its modification strategies of SiO x materials are comprehended and reviewed. [Display omitted] • The factors influencing the failure processes of SiO x have been elaborated. • The synthesis methods classified by raw materials are summarized and re-evaluated. • Techniques to improve the performance of SiO x have been summarized and discussed. • New research directions and future trends have been generally analyzed and elucidated. Silicon oxides (SiO x , 0 ≤ x ≤ 2) have received extensive attention in the field of energy storage due to their high energy density and without the severe volume change of silicon-based anodes. However, the low initial Coulomb efficiency and poor electronic conductivity of SiO x still need to be improved to achieve the satisfactory performance required for commercial applications. In this review, combining the structural feature, electrochemical and failure mechanism of SiO x , the reported synthesis methods classified by raw materials are summarized and re-evaluated, which provides guidelines for selecting appropriate synthesis methods through specific raw materials. Then the latest research progresses of the improvement strategies of SiO x anode are systematically summarized from the perspective of structure design, compounding with the second phase, pre-lithiation and optimization of electrolyte additives or binders. Finally, we discussed the new research directions and future research trends of SiO x materials. This work not only improves the theoretical basis for the preparation and modification of SiO x materials, but also provides direction guidance for accelerating the commercial application of SiO x anode. [ABSTRACT FROM AUTHOR]

Lithium metal batteries are used widely because of their high security and high energy density. However, the solid electrolytes and electrodes have incompatible interfaces, and the lithium anode is also hindered by dendrite growth. Herein, a bifunctional stable electrode interface layer is constructed by in-situ polymerization of polyester-based monomers and organic solvent, revealing the strong correlation between cathode electrolyte interphase (CEI) on cathode and solid electrolyte interface (SEI) on Li metal anode. The sandwich-like composite electrolyte prepared with garnet Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 (LLZTO) active fillers and polymer electrolyte composed of (poly(ethylene glycol) dimethyl ether (PEGDME), trimethylolpropane trimethyllacrylate (TMPTMA), 1,6-hexanediol diacrylate (HDDA)(named as P(PF) 1 TH) exhibits excellent flexibility, wide electrochemical window, and good thermal stability. Moreover, P(PF) 1 TH-10%LLZTO electrolyte has satisfactory ionic conductivity (1.42 × 10−3) at 50 °C and high Li+ transference number (0.547) at 25 °C, and symmetrical Li|P(PF) 1 TH-10%LLZTO|Li cells can run stably for more than 1000 h at 0.1 mA cm−2 at 50 °C. The assembled LiFePO 4 (LEP)|P(PF) 1 TH-10%LLZTO |Li cell shows high discharge capacity of 139.9/122.8 mAh g−1 with capacity retain of 90.64%/97.96% after 200 cycles at 1C/2C. This work introduces a dual functional interface layer between electrolyte and electrode through in-situ polymerization, which brings a new idea for electrode interface compatibility. [Display omitted] • Constructing bi-functional layer between the interface of electrolyte and electrode. • Soft gel layer and garnet-type Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 construct composite electrolyte. • In situ formation of dense and uniform CEI and SEI on LEP and lithium metal. • As-Prepared CSEs have good inhibition on the growth of lithium dendrites. • The matched LFP cathode has stable interface and excellent long-cycle performance. [ABSTRACT FROM AUTHOR]

Edge-N (pyridinic/pyrrolic-N) functionalized carbon is a promising anode for potassium-ion batteries, while micropores have been proven to be effective in increasing capacity and cyclability. However, the obtained carbon materials usually exhibit a low N-doping level and edge-N species based on the conventional pyrolysis method, and the exploration of the synergistic effect of edge-N doping and micropores on the potassium-storage performance is still lacking. Herein, a novel strategy is proposed to prepare edge-N doped carbon (ENC-850) by directly pyrolyzing supermolecule precursors self-assembled by terephthalic acid (BDC) and melamine (MA). Because the s -triazine structure in MA is more stable than BDC, which can easily ensure a higher N-doping content in carbon, and the decomposition of s -triazine structure is accompanied by the release of NCNH 2 gas, which enables most doped N-atoms to be of edge-N configurations, favoring the adsorption storage of K-ions. Besides, the released small molecules can create numerous micropores, not only providing active sites, but accommodating volume fluctuation. Therefore, the optimized ENC-850 with the most suitable edge-N content of 60.6% (7.73 at% of total 11.71 at% N-doping) and micropores delivers a high capacity (280 mAh g−1 at 0.5 A g−1) and superior cycling stability (over 2000 cycles). A novel strategy is proposed to prepare edge-N doped carbon (ENC-850) by directly pyrolyzing supermolecule precursors self-assembled by terephthalic acid (BDC) and melamine (MA), and thus the resulting product delivers an excellent cycling stability. [Display omitted] • A supermolecule precursors self-assembly strategy was proposed based on terephthalic acid (BDC) and melamine (MA). • The unique merits of s -triazine structure enables a higher N-doping content and edge-N species. • The obtained sample delivered an excellent capacity and cycling stability of over 2000 cycles. [ABSTRACT FROM AUTHOR]

Metal sulfides are promising anode materials for sodium-ion batteries (SIBs) due to their structural diversity and high theoretical capacity, but the severe capacity decay and inferior rate capability caused by poor structural stability and sluggish kinetics impede their practical applications. Herein, a cobalt-doped amorphous VS 4 wrapped by reduced graphene oxide (i.e., Co 0.5 -VS 4 /rGO) is developed through a Co-induced defect engineering strategy to boost the kinetics performances. The as-prepared Co 0.5 -VS 4 /rGO demonstrates excellent rate capacities over 10 A g -1 and superior cycling stability at 5 A g -1 over 1600 cycles, which is attributed to the defects formed by Co doping, the formed amorphous structure and the robust rGO substrate. The great features of Co 0.5 -VS 4 /rGO anode are further confirmed in sodium-ion capacitors when the active carbon cathode is used. Additionally, the relationships between metal doping, the derived defects, the amorphous structure, and the sodium storage of VS 4 are uncovered. This work provides deep insights into preparing amorphous functional materials and also probes the potential applications of metal sulfide-based electrode materials for advanced batteries., (© 2024 Wiley‐VCH GmbH.)

Coupling sites of nitrogen-dopants and intrinsic carbon defects (N/DC) are highly attractive to improve potassium-storage capacity and cycling stability, yet it is hard to effectively construct them. Herein, a novel strategy is proposed to establish abundant N/DC sites in N-doped carbon (ZIF8/NaBr-1-900) by pyrolyzing the mixture of metal-organic framework (ZIF8)/sodium bromide (NaBr). Systematic investigations disclose that the introduced NaBr can promote the full conversion of Zn-N 4 moieties into zinc oxide (ZnO) via a "bait and switch" mechanism. Such formed endogenous ZnO can etch the carbon matrix of the confined domains around the N dopants during pyrolysis process, and meanwhile the released N-atoms from Zn-N 4 moieties can largely form edge-N. As such, these N/DC coupling sites enable the resultant carbon to have a more significant capacitive behavior related to fast K-ion migration and high structural stability, leading to 255.3 mAh/g at 2 A/g with a prolonged cycle lifespan over 2000 cycles. Moreover, the assembled K-full battery presents a high energy density of 171.2 Wh kg -1 and excellent cyclability over 5000 cycles. This NaBr-mediated endogenous ZnO domain-confined etching strategy provides a new insight into the exploration of advanced carbon anode., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The mineral formation-transition mechanism, microstructure evolution, crystal structure, pulverization property, and chemical reactivity of the CaO-Al 2 O 3 -SiO 2 clinker with MgO and Na 2 SO 4 dopants during the sintering process at 1300 °C for 2.0 h were systematically studied using CaO, Al 2 O 3 , SiO 2 , MgO, and Na 2 SO 4 as raw materials when the molar ratio of CaO to Al 2 O 3 is 1.4, the mass ratio of Al 2 O 3 to SiO 2 is 3.0, and the mass percentage of MgO and Na 2 SO 4 is 2%. The MgO dopant could result in 12CaO·7Al 2 O 3 and γ-2CaO·SiO 2 , transform into 20CaO·13Al 2 O 3 ·3MgO·3SiO 2 , restrain the crystal transformation of 2CaO·SiO 2 from β to γ, and then deteriorate the pulverization and alumina leaching property corresponding to parts of Al, Si, and Mg atoms occupying the same lattice positions of the crystal structure. MgO and Na 2 SO 4 codoped could promote transformation of 20CaO·13Al 2 O 3 ·3MgO·3SiO 2 into 3CaO·3Al 2 O 3 ·CaSO 4 as well as some 2CaO·Al 2 O 3 ·SiO 2 , while 3CaO·3Al 2 O 3 ·CaSO 4 has good alumina leaching property in the Na 2 CO 3 -NaOH solution. The ultrasonic assistant mainly could promote the diffusion of reactive samples, enhance the separation of agglomeration, and then accelerate the chemical reaction of the sintered clinker with Na 2 CO 3 -NaOH., Competing Interests: The authors declare no competing financial interest.